ANGIOSPERMS, DICOTYLEDONES. 785a schizocarp (CalUtriche; see p. 427, figs. 822= and 322*) or a drupe covered with athin coat of pulp; it becomes detached from the receptacle. In the Water Chestnut(Trapa natans; see vol. i. p. 607, fig. 144) the two whoris of two sepals each whichare adnate to the ovary become a part of the fruit, and their apices project in theform of four stiff points. The Hygrobiae are distributed in every quarter of theglobe, but belong especially to the North Temperate Zone. The Gunneraceaeinhabit the Southern Hemisphere. Fossil remains of a plant resembling Myrio¬phyllum have been found in strata of the Tertiary Period. The number of extantspecies known is about 100. Alliance LXII.—Passiflorales. Families: Passifloraceae, Loasacece, Datiscacece, Samydacece, Turneraceae, Papayaceae. Annual or perennial herbs, shrubs, and trees, with palmately-lobed foUage-leaves.Venation palmate (radiating). Flowers hermaphrodite or pseudo-hermaphrodite,and dioecious; actinomorphic. The floral-leaves spring from a cup-shaped hypan¬thium in one or two 4-5-merous whorls. The gynaeceum is composed of 3 connatecarpels. The unilocular ovary is free, and is raised upon a more or less elongatedstalk from the bottom of the receptacle, or else it is sessile and adnate to the cup-shaped receptacle either half-way from the base or from base to top. The ovulesare borne upon three placentas which project in the form of cushions from theinternal wall of the ovary. The androecium is composed of 4-5 stamens whichspring from the edge of the cup-shaped hypanthium. The fruit is a berry or acapsule opening by valves. The seeds contain a fleshy endosperm, in which isimbedded a straight embryo. The Datiscaceae have a sepaloid perianth. In the Loasaceae and Passifloraceaethe floral-leaves are in two whorls, both of which are petaloid. In the Passifloraceaea many-membered corona is inserted between the androecium and the petals.The Paissiflorales belong chiefly to tropical America. Fossil remains have not beenidentified with certainty. The number of extant species known is about 700. Alliance LXIII.—Pepones. Families: Cucurbitaceae and Begoniacece. Annual and perennial herbs and under-shrubs (suffrutices). Venation of thefoliage-leaves radiating (palmate). Flowers solitary or in cymes; actinomorphic;pseudo-hermaphrodite, monoecious and dioecious. The uppermost part of the ,receptacle, which is deeply hollowed, is developed as a hypanthium, and from itspring the fioral-leaves in 1-2 whorls of 2-5 segments each. When two whoris arepresent they are either both petaloid in colour or the under whorl is a calyx and theupper a corolla. The petals are either free or partially coherent. The ovary isinferior. The ovules are borne on thick pads which are split in two longitudinally. Vol, II. 100